M.O. of perp: strangulation, no sexual penetration, torture – cuts, sprayed with perfume, clothes and possessions removed.

On Jessica’s side, he wrote some extra details: her injuries were worse, displaying an escalation in violence. The cuts were deeper and, according to Daniel Hamlet, had been inflicted with more force. Jess had bruises on her face; some of her hair had been yanked out. Why was this? Had she fought, made him angry? Was it the kind of escalation sometimes seen in serial murders, where the killer got more extreme as he went along, more confident and frenzied, needing the greater violence to feel satisfied? Or had he hated Jessica more than he hated Rose?

Patrick pondered this last question. How had the killer chosen these two victims? Were the girls interchangeable or had they been targeted specifically?

He wrote this down too, with a thick question mark that made him itch with frustration. From what Wendy and Martin had found out so far, there was no sign of them interacting online except in the most superficial way. They had both tweeted and written about the same subjects, namely how much they loved Shawn, how amazing the last OnT video was, how much they despised a Daily Mail journalist who had interviewed the band and described them as ‘vacuous puppies without the guts or gumption to say a single interesting thing’. The only thing that set them apart from a hundred thousand other OnT fans was the level of their online activity. They were – what did Wendy call them? – super users.

What were the other differences and similarities? Rose was found in a hotel; Jessica in a photo studio. They knew the studio had once been used by OnTarget, but there appeared to be no connection between the Travel Inn and the band. They had never stayed there, not in this or any other branch. No-one at the hotel had any connection to the band. So why had the killer chosen the photo studio, with its direct connection, and the hotel, which had none? The use of the perfume suggested deliberate symbolism. It seemed he wanted it to be known that their fandom had made them targets. Or was it, as Carmella had pointed out, just that both girls had been carrying the fragrance with them? Their mothers had confirmed that they both owned a bottle of Friendship. Maybe that was all it was.

Maybe, Patrick thought with a start, the fact that they were both OnTarget fans was a red herring. Could that be possible? After all, a large percentage of teenage girls in this country liked OnT.

He spotted Wendy at the other end of the office and called her over.

‘All right?’ she said. She seemed a little wary, like an office worker who’s been summoned by their boss, but, more than that, she looked tired. Knowing her exhaustion was caused by the long hours she’d been putting in, Patrick felt more pleasure than sympathy, sure that Wendy was going to make an excellent officer when she got some more experience under her belt. With her youthful looks and Black Country accent, Wendy struggled to be taken seriously. Patrick, with his tattoos, could empathise with that.

‘Wendy,’ he said. ‘I need to know if there’s any connection between the Travel Inn and OnTarget.’ He summarised what they knew so far. ‘Any ideas?’

She pondered a moment and then asked, ‘What room was Rose found in?’

‘Three-six-five.’

She snapped her fingers in triumph. ‘Thought it might be.’

‘Eh?’

‘“Room 365” is the title of an OnTarget song. It’s on the first album. It’s about wanting to lock yourself away with a girl 365 days of the year.’ She sang a snatch of the song, her voice sweet and tuneful. ‘And my baby comes alive/In room three-sixty-five, three-sixty-five.’

Patrick stared at her. ‘Why didn’t anyone else know that?’

Wendy gave him a little shrug. ‘You obviously didn’t ask the right person.’

He grinned at her and she appeared delighted to have been so helpful.

‘How are you getting on?’ With the new focus on Shawn Barrett, Patrick had lost track of what Wendy was up to. ‘I assume you haven’t found any direct connections between Rose and Jessica online yet? Nothing on the forums? Or on their computers?’

‘Nothing direct.’ Her eyelashes fluttered nervously. ‘But I am making good progress. I’m getting to know the girls who use the OnT forum, the other super users, gaining their trust. I’m pretty much ready to start a conversation about Rose and Jess now. I just need a couple more days.’

Patrick tapped his fingers on the desk. Was this a waste of time? Maybe it would be better to pull her off this task. Winkler kept going on about how he needed someone to help him with, as he put it, the donkey work. He would hate to bestow that fate upon her, but . . .

‘Please, Patrick.’

He looked up sharply.

‘Sorry, I meant, sir.’

‘It’s OK. You can call me Patrick when it’s just the two of us around. Or “boss”, if you prefer.’

She turned pink and met his eye and he realised his words had come out wrong.

Embarrassed, he said, ‘OK, it’s fine. If you’re sure you’re getting close. But if it seems like these young women don’t know anything useful, I want you working on something else.’

‘Of course. Thanks, er, Patrick.’

‘Any decision I make is for the sake of the case, so you don’t need to thank me.’

She deepened from pink to red, as bad as Gareth Batey, who was renowned for his blushes. Patrick sighed, wishing he could shake this prickly, irritated mood.

‘Listen, you look shattered. When did you last go home?’

‘Um. I can’t remember. Yesterday?’

‘Right. Well, take a few hours, go home, have a nap. I think you’ve earned a break.’

‘But I want to stay here and—’

‘Wendy, I’m ordering you to go home. OK?’

She opened her mouth to argue, but shut it again. ‘Thanks, boss.’

After she’d gone, he returned to his notebook, adding in what Wendy had told him about the ‘Room 365’ song, which seemed to eradicate any last doubt that OnTarget was the link here. He checked his mobile again. Still nothing from Carmella, just two more texts from Gill, telling him she had decided not to go to the meeting with her old firm because she had a headache, and that she’d called Patrick’s mum and asked her if she could drop off Bonnie for a couple of hours. For fuck’s sake! He thumped the mobile down on the desk, just as Gareth Batey walked into the office.

‘Boss,’ said Gareth, hovering sheepishly at the edge of the room.

Patrick looked up at him, frustration and irritation scratching at his skin. ‘Yes?’

‘I’ve been round all the fast-food places near the Travel Inn, like you asked. There are dozens of them and they all have tons of staff, most of whom work shifts, half of them not officially on the books, so trying to talk to anyone has been a total—’

‘Just cut to the chase. Does anyone remember seeing Rose that night?’

‘Well, no, but one guy thought he remembered seeing a girl wearing an OnTarget hoodie . . .’

‘Rose wasn’t wearing a hoodie.’

‘I know, but—’

‘So why are you telling me this utterly useless piece of information? And what’s going on with this key card? Has Peter Bell got back to you yet?’

‘I haven’t had a chance to chase him, boss, because I’ve been trudging round burger bars in Teddington.’

Patrick glared at him. His impatience with the case; waiting for Carmella to call; everything that was going on with Gill . . . It was rare for Patrick to lose his temper, but right now he felt like a bunch of toddlers were tugging on his nerve endings, shrieking, and it took every ounce of self-control not to point a finger at Gareth and yell, ‘Haven’t had a chance? I thought you took this job seriously? Get the fuck out of my sight and don’t come back until Peter fucking Bell has told you everything he knows about hackers and fucking hotel key cards and . . .’